An analytical method, referred to as "derivatization-electron probe X-ray micro-analysis (XMA)", has been developed to determine the distribution of a small amount of the functional groups in a polymer. The suitable conditions for the derivatization reaction with epoxy groups, which contribute to the hardening reactions of polymers, were investigated. It was found that epoxy groups in polymers ...

The role of elastic mismatch in determining critical conditions for indentation fracture in brittle coatings on substrates of unlike modulus was investigated. A model transparent trilayer system, consisting of a glass coating layer bonded to a thick substrate of different glass or polymer by a thin layer of epoxy adhesive, facilitated in situ observations of crack initiation and propagation. A ...

Effect of zirconia nanoparticles (zirconia NPs/ZrO2 NPs) modified by 3 wt.% (glycidyloxypropyl) triethoxysilane – GPTES (m-ZrO2 on some properties epoxy coating such as mechanical properties, thermal stability and anti-corrosion performance was investigated. The obtained results indicated that the addition to could enhance this coating. 2 pure ZrO2 NPs (u-ZrO2 matrix increase (hardness adhesion...

Severe corrosion of epoxy coated rebar in the substructure of 5 major marine bridges in the Florida Keys was detected after only a few years of construction. Corrosion occurred underneath the coating and was preceded by loss of adherence between the steel and the coating. Damage surveys of the bridges, which were built around 1980, were conducted from 1986 to 2000. Corrosion resulted in delamin...

The surface characteristics of an aluminium alloy treated with a commercial chromate pretreatment have been studied by SAM, EDX and XPS. XPS indicates that the chromium is present in the conversion coating as both Cr(III) and Cr(VI) species, and that other components are present at the conversion coating surface, some in a reduced form. The deposition of the chromate layer is compromised by the...

Self-healing polymers composed of microencapsulated healing agents exhibit remarkable mechanical performance and regenerative ability, but are limited to autonomic repair of a single damage event in a given location. Self-healing is triggered by crack-induced rupture of the embedded capsules; thus, once a localized region is depleted of healing agent, further repair is precluded. Re-mendable po...

Epoxy coatings are usually reinforced by the use of nanofillers, but reactive nanofillers having physical tendency towards epoxide ring opening are preferable. In this work, nanosilica (SiO2) and halloysite nanotubes (HNTs) known for their hydroxyl-contained surface are used and their effects on the curing behavior of an epoxy/amine coating is compared. The spherical and tubular nano...